High-gain wideband circularly polarized resonant cavity antenna

This paper presents a high gain wideband circularly polarized (CP) resonant cavity antenna. The primary radiators consist of two orthogonal bowtie dipoles, which generate wideband CP radiation. High-gain broadside radiation and wide axial ratio (AR) bandwidth are achieved with the properly chosen lateral size of a half-wavelength-thick planar partially reflecting surface. The antenna with an overall size of 80 mm × 80 mm × 28.35 mm yields ™10-dB impedance, 3-dB AR, and 3-dB gain bandwidths of 40%, 25.6%, and 42.7%, respectively.